Question

7a-4b=5; 3a+2b=17 solve the simultaneous equations​

Answer 1

Step-by-step explanation:

$7a - 4b = 5$

$3a + 2b = 17$

multiply in equations (1) by 2

$7a - 4b = 5$

$6a + 4b = 34$

$13a = 39$

$a = 3$

$21 - 4b = 5$

$16 = 4b$

$b = \frac{16}{4} = 4$

Answer 2

Answer:

7 a - 4b = 5 ---(1)

3a + 2b= 17 ----(2)

multiplying eq (2) from 2

6a +4b=34-----(3)

now adding eq (1) and(3)

7a-4b+6a+4b =5+ 34

13 a = 39

a = 39/13

a = 3

putting the value of a in eq (1)

7a- 4b = 5

7×3 - 4b = 5

21 - 4b = 5

21 -5 =4b

16 = 4b

b= 16/4

b = 4

a =3, b=4